HELP! Error Message

when loading my Learn Direct CD-rom it keeps coming up with this error message:Runtime error:2147467259(80004005);specified driver could not be loaded due to system error 1157(microsoft Access Driver)(*.Mdb)).Have tried asking Microsoft Word & Learn Direct helpline - no joy. Does anyone out there know what's going on? I am sure it is to do with me, when I first got our computer a few months ago I was fiddling about on programmes& I think I must have done something to get this error.Please try & let me know what I have done or who I should contact to resolve this.Thanks for reading this long-winding question(if you got this far!)